System and method for patient-side instrument control

ABSTRACT

A surgical instrument is configured to be installed for use on a teleoperated surgical system. A surgeon or other medical person controls the surgical instrument by manipulating one or more control inputs. Computer-assisted teleoperated actuators of the teleoperated surgical system move one or more surgical instrument mechanical degrees of freedom in response to movements of the one or more control inputs. A teleoperated surgical system is provided to enable a surgeon or medical person to manually control one or more surgical instrument mechanical degrees of freedom, while the surgical instrument is installed for use on the teleoperated surgical system.

RELATED APPLICATION

This patent application is a U.S. National Stage patent application ofInternational Patent Application No. PCT/US2016/036849 (filed on Jun.10, 2016), the benefit of which is claimed, and claims priority to andthe benefit of the filing date of U.S. Provisional Patent Application62/173,856, entitled “SYSTEM AND METHOD FOR PATIENT-SIDE INSTRUMENTCONTROL” filed Jun. 10, 2015, each of which is incorporated by referenceherein in its entirety.

COPYRIGHT NOTICE

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by any-one of the patentdocument or the patent disclosure, as it appears in the Patent andTrademark Office patent file or records, but otherwise reserves allcopyright rights whatsoever.

BACKGROUND 1. Field of Invention

The inventive aspects disclosed here relate generally to the operationof a teleoperated surgical system, and more specifically, to a controlalgorithm implemented on a teleoperated surgical system that enablesmanual control of a teleoperated surgical instrument from the patientside.

2. Art

A teleoperated surgical system including one or more computer-controlledmotors can allow a medical person to remotely control a surgicalinstrument. Some teleoperated surgical systems include a surgeon'sconsole housing one or more control inputs in communication with the oneor more computer-controlled motors. The surgeon's console canadditionally include a video display that is in communication with acamera located at a surgical site. The computer-controlled motors movein response to the medical person's control of the one or more controlinputs while viewing the video display. The motions of thecomputer-controlled motors operate a surgical instrument coupled to themotors.

In some cases, it is desirable to provide a means of controlling saidsurgical instrument to someone other than the medical person seated asurgeon's console. One example of a situation in which this additionalmeans of control is desirable is in an emergency situation. In anemergency situation, the medical person seated at the surgeon's consoleis not located immediately beside the patient undergoing surgicaltreatment. In such a situation, a medical person located beside thepatient (i.e., located at the patient side) may be better ablecoordinate with other medical persons to quickly remedy the emergencysituation.

Surgical instruments provided for use with a teleoperated surgicalsystem generally include an end effector. The end effector is thebusiness end of the surgical instrument that performs the tasksassociated of a surgical procedure. Examples of various types of endeffectors include forceps, graspers, scissors, needle drivers, and thelike. Often, specific forceps and graspers are purposed specifically tosecurely grasp patient tissue, for example to enable retraction oftissue during a surgical procedure that would otherwise block asurgeon's view of other tissue of interest.

In certain cases, an emergency situation arises at a time when asurgical instrument on a teleoperated surgical system is securelygrasping tissue. Sometimes remedying the emergency situation requiresremoval of the surgical instrument from the surgical field. In thesecases, it is desirable to provide a medical person located at thepatient side with a means to release the surgical instrument's grasp ofpatient tissue before the surgical instrument is removed, so as to notcause damage to grasped tissue and surrounding anatomy.

SUMMARY

The following summary introduces certain aspects of the inventivesubject matter in order to provide a basic understanding. This summaryis not an extensive overview of the inventive subject matter, and it isnot intended to identify key or critical elements or to delineate thescope of the inventive subject matter. Although this summary containsinformation that is relevant to various aspects and embodiments of theinventive subject matter, its sole purpose is to present some aspectsand embodiments in a general form as a prelude to the more detaileddescription below.

In one aspect, an algorithm executed by a teleoperated surgical systemenables a user to manually control a teleoperated surgical instrumentfrom the patient side. The teleoperated surgical system includes a firstteleoperated actuator configured to actuate a first mechanical degree offreedom of the surgical instrument and a second teleoperated actuatorconfigured to actuate a second mechanical degree of freedom of thesurgical instrument. While the first teleoperated actuator is beingcommanded to maintain its current position, an application of anexternal force that is in excess of a first force threshold is detected.Meanwhile, at the second teleoperated actuator, which is being commandedto maintain its current position, no application of external force thatis in excess of a second force threshold is detected. Upon detectingthese conditions, the command to the first teleoperated actuator tomaintain its current position is terminated.

In another aspect, a medical device includes a control input and amanipulator including a first teleoperated actuator and a secondteleoperated actuator. The instrument manipulator is configured toreceive a surgical instrument. The first teleoperated actuator isconfigured to actuate a first mechanical degree of freedom of thesurgical instrument and the second teleoperated actuator is configuredto actuate a second degree of freedom of the surgical instrument. Acontroller of the medical device is configured to control movement ofthe surgical instrument in response to movement of the control input.The controller is further configured to detect, while the firstteleoperated actuator is being commanded to maintain its currentposition, an application of an external force to the first teleoperatedactuator that is in excess of a first force threshold. Additionally, thecontroller is configured to detect, while the a second teleoperatedactuator being teleoperated to maintain its current position, noapplication of external force to the second teleoperated actuator thatis in excess of a second force threshold. Upon detecting theseconditions, the controller is configured to terminate the command to thefirst teleoperated actuator to maintain its current position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a minimally invasive teleoperated surgicalsystem.

FIG. 2 is a perspective view of a surgeon's console.

FIG. 3 is a perspective view of an electronics cart.

FIG. 4 is a diagrammatic illustration of a teleoperated surgical system.

FIG. 5 is a perspective view of a patient-side cart.

FIG. 6 is an elevation view of a surgical instrument.

FIG. 7 is a perspective view of an instrument manipulator.

FIG. 8A is a schematic diagram of a control algorithm that enablespatient side control of a teleoperated surgical instrument.

FIG. 8B is a schematic diagram of a control algorithm that enablespatient side control of a teleoperated surgical instrument.

FIG. 9A is perspective view of a proximal control portion of a surgicalinstrument.

FIG. 9B is a proximal control portion of a surgical instrument viewedfrom the distal direction.

FIG. 10A is a perspective view of a proximal control portion of asurgical instrument.

FIG. 10B is a perspective view of a proximal portion of a surgicalinstrument with its exterior cover removed.

FIG. 10C is a proximal control portion of a surgical instrument viewedfrom the distal direction.

FIG. 11A is a perspective view of a proximal control portion of asurgical instrument.

FIG. 11B is a perspective view of a proximal portion of a surgicalinstrument with its exterior cover shown transparently.

FIG. 11C is a proximal control portion of a surgical instrument viewedfrom the distal direction.

FIG. 12A is a perspective view of a proximal control portion of asurgical instrument.

FIG. 12B is a perspective view of a proximal portion of a surgicalinstrument with its exterior cover removed.

FIG. 12C is a proximal control portion of a surgical instrument viewedfrom the distal direction.

DETAILED DESCRIPTION

This description and the accompanying drawings that illustrate inventiveaspects, embodiments, implementations, or applications should not betaken as limiting—the claims define the protected invention. Variousmechanical, compositional, structural, electrical, and operationalchanges may be made without departing from the spirit and scope of thisdescription and the claims. In some instances, well-known circuits,structures, or techniques have not been shown or described in detail inorder not to obscure the invention. Like numbers in two or more figuresrepresent the same or similar elements.

Further, this description's terminology is not intended to limit theinvention. For example, spatially relative terms—such as “beneath”,“below”, “lower”, “above”, “upper”, “proximal”, “distal”, and thelike—may be used to describe one element's or feature's relationship toanother element or feature as illustrated in the figures. Thesespatially relative terms are intended to encompass different positions(i.e., locations) and orientations (i.e., rotational placements) of adevice in use or operation in addition to the position and orientationshown in the figures. For example, if a device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be “above” or “over” the other elements or features.Thus, the exemplary term “below” can encompass both positions andorientations of above and below. A device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly. Likewise, descriptionsof movement along and around various axes includes various specialdevice positions and orientations. In addition, the singular forms “a”,“an”, and “the” are intended to include the plural forms as well, unlessthe context indicates otherwise. And, the terms “comprises”,“comprising”, “includes”, and the like specify the presence of statedfeatures, steps, operations, elements, and/or components but do notpreclude the presence or addition of one or more other features, steps,operations, elements, components, and/or groups. Components described ascoupled may be electrically or mechanically directly coupled, or theymay be indirectly coupled via one or more intermediate components.

Elements described in detail with reference to one embodiment,implementation, or application may, whenever practical, be included inother embodiments, implementations, or applications in which they arenot specifically shown or described. For example, if an element isdescribed in detail with reference to one embodiment and is notdescribed with reference to a second embodiment, the element maynevertheless be claimed as included in the second embodiment. Thus, toavoid unnecessary repetition in the following description, one or moreelements shown and described in association with one embodiment,implementation, or application may be incorporated into otherembodiments, implementations, or aspects unless specifically describedotherwise, unless the one or more elements would make an embodiment orimplementation non-functional, or unless two or more of the elementsprovide conflicting functions.

Aspects of the invention are described primarily in terms of animplementation using a da Vinci® Surgical System (specifically, a ModelIS4000, marketed as the da Vinci® Xi™ HD™ Surgical System),commercialized by Intuitive Surgical, Inc. of Sunnyvale, Calif.Knowledgeable persons will understand, however, that inventive aspectsdisclosed herein may be embodied and implemented in various ways,including robotic and, if applicable, non-robotic embodiments andimplementations. Implementations on da Vinci® Surgical Systems (e.g.,the Model IS3000, commercialized as the da Vinci® Si™ HD™ SurgicalSystem; the Model IS2000, commercialized as the da Vinci® S™ HD™Surgical System) are merely exemplary and are not to be considered aslimiting the scope of the inventive aspects disclosed herein.

As used here, the term “back-drive” shall describe a situation in whichan external force applied to an output component is transmitted, eitherdirectly or through an intermediate mechanism, to an input component.The terms “input component” and “output component” are descriptive ofthe function served by a given component under normal operation. Duringnormal operation, the direction of force transmission is typically frominput component to output component. This force transmission from inputcomponent to output component can be described as forward-driving themechanism. Back-driving, thus, is the opposite of forward-driving.

As an example, a surgical instrument that is used with a teleoperatedsurgical system can forward-driven in the following manner. The surgicalinstrument can include an input component and an output component.During normal operation of the surgical instrument, a force applied tothe input component of the surgical instrument is transmitted by atransmission mechanism (e.g., gears, pulleys, pullwires, etc.) to anoutput component of the surgical instrument. The force applied to theinstrument input can be applied by a teleoperated actuator of ateleoperated surgical system. In one example, the input component is arotary input of the surgical instrument (“instrument input”), and theoutput component is component of a surgical instrument end effector suchas movable jaw member. A mechanical force that is applied to theinstrument input can be transmitted, e.g., by a pullwire, to move themovable jaw member. In another example, the input component is aninstrument input, and the output component is a component of anorientable wrist coupled to the instrument input through one or morepullwires. During normal operation, a mechanical force that is appliedto the instrument input is be transmitted through one or more pullwiresto move the component of the orientable wrist.

In one aspect, one or more mechanical degrees of freedom of the surgicalinstrument described above can also be back-driven. As used here,back-driving is the opposite of forward-driving. In one example, aninstrument input that is coupled to a movable jaw member by one or morepullwires can be back-driven by a force applied to the movable jawmember. When this back-driving takes place, the force applied to themovable jaw member is transmitted by the one or more pullwire to theinstrument input. In one example, the instrument input is a rotary inputof the surgical instrument, and the force applied to the movable jawmember rotates the instrument input relative to the rest of the surgicalinstrument. In one aspect, this surgical instrument is coupled to aninstrument manipulator of a teleoperated surgical system, and theinstrument input is mechanically coupled to a teleoperated instrumentactuator. In this situation, the force applied to the movable jaw membercan be further transmitted to the teleoperated actuator.

With reference to the surgical instrument described above, in oneaspect, the movable jaw member and the instrument input that is coupledto the movable jaw member are both additionally coupled to a mechanicalfeature for manual actuation of the movable jaw member. In one case,this mechanical feature for manual actuation of the movable jaw memberis configured to be kinematically downstream of the instrument input,and involves part of the transmission mechanism that couples theinstrument input to the movable jaw. For example, the mechanical featurecan be a lever that is mechanically coupled to one or more elements ofthe transmission mechanism. Accordingly, an external force applied tothe lever is transmitted to the transmission mechanism, which in turntransmits this force to the movable jaw member. Alternatively, themechanical feature can be a keying feature that is mechanically coupledto elements of the transmission mechanism. Accordingly, an externalforce applied to the keying feature can be transmitted to thetransmission mechanism, which in turn transmits this force to themovable jaw member.

As discussed previously, in one aspect, this mechanical feature iscoupled to the instrument input in addition to the movable jaw member.Accordingly, if an external force is applied to the mechanical feature,the transmission mechanism transmits this force to the instrument inputin addition to the movable jaw member. This transmission of force fromthe mechanical feature to the instrument input is one example ofback-driving the instrument input.

It is worth noting that not all mechanism that can be forward-driven arecapable of being back-driven. One example of a mechanism that cannot beback-driven is a drive mechanism including a lead screw and a drivennut. The leadscrew is typically configured to permit only rotationalmotion (i.e., it is restrained from translating). Typically, thismechanism is forward-driven by rotating the leadscrew relative to thedriven nut. The rotation of the leadscrew relative to the nut translatesthe nut along a longitudinal axis of the leadscrew. This mechanism,however, is generally incapable of being backdriven. Said another way,one cannot try translate the driven nut along the longitudinal axis ofthe leadscrew to cause a rotation of the leadscrew.

Minimally Invasive Teleoperated Surgical System

Referring now to the drawings, in which like reference numeralsrepresent like parts throughout the several views, FIG. 1 is a plan viewof a minimally invasive teleoperated surgical system 10, typically usedfor performing a minimally invasive diagnostic or surgical procedure ona patient 12 who is lying on an operating table 14. The system includesa surgeon's console 16 for use by a surgeon 18 during the procedure. Oneor more assistants 20 may also participate in the procedure. Theminimally invasive teleoperated surgical system 10 further includes apatient-side cart 22 and an electronics cart 24. The patient-side cart22 can manipulate at least one removably coupled instrument 26 through aminimally invasive incision in the body of the patient 12 while thesurgeon 18 views the surgical site through the surgeon's console 16. Animage of the surgical site can be obtained by an endoscope 28, such as astereoscopic endoscope, which can be manipulated by the patient-sidecart 22 to orient the endoscope 28. Computer processors located on theelectronics cart 24 can be used to process the images of the surgicalsite for subsequent display to the surgeon 18 through the surgeon'sconsole 16. The number of surgical instruments 26 used at one time willgenerally depend on the diagnostic or surgical procedure and the spaceconstraints within the operating room among other factors. If it isnecessary to change one or more of the instruments 26 being used duringa procedure, an assistant 20 can remove the instrument 26 from thepatient-side cart 22, and replace it with another instrument 26 from atray 30 in the operating room.

FIG. 2 is a perspective view of the surgeon's console 16. The surgeon'sconsole 16 includes a left eye display 32 and a right eye display 34 forpresenting the surgeon 18 with a coordinated stereoscopic view of thesurgical site that enables depth perception. The console 16 furtherincludes one or more input control devices 36. One or more instrumentsinstalled for use on the patient-side cart 22 (shown in FIG. 1) move inresponse to surgeon 18's manipulation of the one or more input controldevices 36. The input control devices 36 can provide the same mechanicaldegrees of freedom as their associated surgical instruments 26 (shown inFIG. 1) to provide the surgeon 18 with telepresence, or the perceptionthat the input control devices 36 are integral with the instruments 26so that the surgeon has a strong sense of directly controlling theinstruments 26. To this end, position, force, and tactile feedbacksensors (not shown) may be employed to transmit position, force, andtactile sensations from the surgical instruments 26 back to thesurgeon's hands through the input control devices 36.

The surgeon's console 16 is usually located in the same room as thepatient so that the surgeon can directly monitor the procedure, bephysically present if necessary, and speak to a patient-side assistantdirectly rather than over the telephone or other communication medium.But, the surgeon can be located in a different room, a completelydifferent building, or other remote location from the patient allowingfor remote surgical procedures.

FIG. 3 is a perspective view of the electronics cart 24. The electronicscart 24 can be coupled with the endoscope 28 and includes a processor toprocess captured images for subsequent display, such as to a surgeon onthe surgeon's console, or on another suitable display located locallyand/or remotely. For example, if a stereoscopic endoscope is used, aprocessor on electronics cart 24 can process the captured images topresent the surgeon with coordinated stereo images of the surgical site.Such coordination can include alignment between the opposing images andcan include adjusting the stereo working distance of the stereoscopicendoscope. As another example, image processing can include the use ofpreviously determined camera calibration parameters to compensate forimaging errors of the image capture device, such as optical aberrations.Optionally, equipment in electronics cart may be integrated into thesurgeon's console or the patient-side cart, or it may be distributed invarious other locations in the operating room.

FIG. 4 diagrammatically illustrates a teleoperated surgical system 50(such as the minimally invasive teleoperated surgical system 10 of FIG.1). As discussed above, a surgeon's console 52 (such as surgeon'sconsole 16 in FIG. 1) can be used by a surgeon to control a patient-sidecart 54 (such as patent-side cart 22 in FIG. 1) during a minimallyinvasive procedure. The patient-side cart 54 can use an imaging device,such as a stereoscopic endoscope, to capture images of a surgical siteand output the captured images to a computer processor located on anelectronics cart 56 (such as the electronics cart 24 in FIG. 1). Theprocessor typically includes one or more data processing boards purposedfor executing computer readable code stored in a non-volatile memorydevice of the processor. In one aspect, the processor can process thecaptured images in a variety of ways prior to any subsequent display.For example, the processor can overlay the captured images with avirtual control interface prior to displaying the combined images to thesurgeon via the surgeon's console 52.

Additionally or in the alternative, the captured images can undergoimage processing by a processor located outside of electronics cart 56.In one aspect, teleoperated surgical system 50 includes an optionalprocessor 58 (as indicated by dashed line) similar to the processorlocated on electronics cart 56, and patient-side cart 54 outputs thecaptured images to processor 58 for image processing prior to display onthe surgeon's console 52. In another aspect, captured images firstundergo image processing by the processor on electronics cart 56 andthen undergo additionally image processing by processor 58 prior todisplay on the surgeon's console 52. In one aspect, teleoperatedsurgical system 50 includes an optional display 60, as indicated bydashed line. Display 60 is coupled with the processor located on theelectronics cart 56 and with processor 58, and captured images processedby these processors can be displayed on display 60 in addition to beingdisplayed on a display of the surgeon's console 52.

FIG. 5 is a perspective view of a patient-side cart 500 of a minimallyinvasive teleoperated surgical system, in accordance with embodiments ofthe present invention. The patient-side cart 500 includes one or moresupport assemblies 510. A surgical instrument manipulator 512 is mountedat the end of each support assembly 510. Additionally, each supportassembly 510 can optionally include one or more unpowered, lockablesetup joints that are used to position the attached surgical instrumentmanipulator 512 with reference to the patient for surgery. As depicted,the patient-side cart 500 rests on the floor. In other embodiments,operative portions of the patient-side cart can be mounted to a wall, tothe ceiling, to the operating table 526 that also supports the patient'sbody 522, or to other operating room equipment. Further, while thepatient-side cart 500 is shown as including four surgical instrumentmanipulators 512, more or fewer surgical instrument manipulators 512 maybe used.

A functional minimally invasive teleoperated surgical system willgenerally include a vision system portion that enables the operator toview the surgical site from outside the patient's body 522. The visionsystem typically includes a camera instrument 528 for capturing videoimages and one or more video displays for displaying the capturedimages. In some surgical system configurations, the camera instrument528 includes optics that transfer the images from the distal end of thecamera instrument 528 to one or more imaging sensors (e.g., CCD or CMOSsensors) outside of the patient's body 522. Alternatively, the imagingsensor(s) can be positioned at the distal end of the camera instrument528, and the signals produced by the sensor(s) can be transmitted alonga lead or wirelessly for processing and display on the one or more videodisplays. An illustrative video display is the stereoscopic display onthe surgeon's console in surgical systems commercialized by IntuitiveSurgical, Inc., Sunnyvale, Calif.

Referring to FIG. 5, mounted to each surgical instrument manipulator 512is a surgical instrument 520 that operates at a surgical site within thepatient's body 522. Each surgical instrument manipulator 512 can beprovided in a variety of forms that allow the associated surgicalinstrument to move with one or more mechanical degrees of freedom (e.g.,all six Cartesian degrees of freedom, five or fewer Cartesian degrees offreedom, etc.). Typically, mechanical or control constraints restricteach manipulator 512 to move its associated surgical instrument around acenter of motion on the instrument that stays stationary with referenceto the patient, and this center of motion is typically located at theposition where the instrument enters the body.

In one aspect, surgical instruments 520 are controlled throughcomputer-assisted teleoperation. A functional minimally invasiveteleoperated surgical system includes a control input that receivesinputs from a user of the teleoperated surgical system (e.g., a surgeonor other medical person). The control input is in communication with oneor more computer-controlled teleoperated actuators, to which surgicalinstrument 520 is coupled. In this manner, the surgical instrument 520moves in response to a medical person's movements of the control input.In one aspect, one or more control inputs are included in a surgeon'sconsole such as surgeon's console 16 shown at FIG. 2. A surgeonmanipulates input control devices 36 of surgeon's console 16 to operateteleoperated actuators of patient-side cart 500. The forces generated bythe teleoperated actuators are transferred via drivetrain mechanisms,which transmit the forces from the teleoperated actuators to thesurgical instrument 520.

Referring to FIG. 5, in one aspect, a surgical instrument 520 and acannula are removably coupled to the distal end of manipulator 512, withthe surgical instrument 520 inserted through the cannula 524. One ormore teleoperated actuators of the manipulator 512 move the surgicalinstrument 512 as a whole. The manipulator 512 further includes aninstrument carriage 530. The surgical instrument 520 is detachablyconnected to the instrument carriage 530. In one aspect, the instrumentcarriage 530 houses one or more teleoperated actuators that provide anumber of controller motions that the surgical instrument 520 translatesinto a variety of movements of an end effector on the surgicalinstrument 520. Thus the teleoperated actuators in the instrumentcarriage 530 move only one or more components of the surgical instrument520 rather than the instrument as a whole. Inputs to control either theinstrument as a whole or the instrument's components are such that theinput provided by a surgeon or other medical person to the control input(a “master” command) is translated into a corresponding action by thesurgical instrument (a “slave” response).

In an alternate embodiment, instrument carriage 530 does not houseteleoperated actuators. Teleoperated actuators that enable the varietyof movements of the end effector of the surgical instrument 520 arehoused in a location remote from the instrument carriage 530, e.g.,elsewhere on patient-side cart 500. A cable-based force transmissionmechanism or the like is used to transfer the motions of each of theremotely located teleoperated actuators to a correspondinginstrument-interfacing output located on instrument carriage 530.

FIG. 6 is a side view of a surgical instrument 520, comprising a distalportion 650 and a proximal control mechanism 640 coupled by an elongatetube 610 having an elongate tube centerline axis 611. The surgicalinstrument 520 is configured to be inserted into a patient's body andused to carry out surgical or diagnostic procedures. The distal portion650 of the surgical instrument 520 can provide any of a variety of endeffectors 654, such as the forceps shown, a needle driver, a cauterydevice, a cutting tool, an imaging device (e.g., an endoscope orultrasound probe). In the embodiment shown, the end effector 654 iscoupled to the elongate tube 610 by a wrist 652 that allows theorientation of the end effector to be manipulated with reference to theelongate tube centerline axis 611. Further, many surgical end effectorsinclude a functional mechanical degree of freedom, such as jaws thatopen or close, or a knife that translates along a path. Surgicalinstruments may also contain stored (e.g., on a semiconductor memoryinside the instrument) information that may be permanent or may beupdatable by the surgical system. Accordingly, the system may providefor either one-way or two-way information communication between theinstrument and one or more system components.

FIG. 7 is a perspective view of surgical instrument manipulator 512,which is also shown in FIG. 5 Instrument manipulator 512 is shown withno surgical instrument installed. Instrument manipulator 512 includes aninstrument carriage 530 to which a surgical instrument can be detachablyconnected. Instrument carriage 530 houses a plurality of teleoperatedactuators (not shown). Each teleoperated actuator includes an actuatoroutput 705. When a surgical instrument is installed onto instrumentmanipulator 512, one or more instrument inputs (not shown) of aninstrument proximal control mechanism (e.g., proximal control mechanism640 at FIG. 6) are mechanically coupled with corresponding actuatoroutputs 705. In one aspect, this mechanical coupling is direct, withactuator outputs directly contacting corresponding instrument inputs. Inanother aspect, this mechanical coupling occurs through an intermediateinterface, such as a component of a drape configured to provide asterile barrier between the instrument manipulator 512 an associatedsurgical instrument.

In one aspect, movement of one or more instrument inputs bycorresponding teleoperated actuators results in a movement of a surgicalinstrument mechanical degree of freedom. For example, in one aspect, thesurgical instrument installed on instrument manipulator 512 is surgicalinstrument 520, shown at FIG. 6. Referring to FIG. 6, in one aspect,movement of one or more instrument inputs of proximal control mechanism640 by corresponding teleoperated actuators rotates elongate tube 610(and the attached wrist 652 and end effector 654) relative to theproximal control mechanism 640 about elongate tube centerline axis 611.In another aspect, movement of one or more instrument inputs bycorresponding teleoperated actuators results in a movement of wrist 652,orienting the end effector 654 relative to the elongate tube centerlineaxis 611. In another aspect, movement of one or more instrument inputsby corresponding teleoperated actuators results in a movement of one ormore moveable elements of the end effector 654 (e.g., a jaw member, aknife member, etc.). Accordingly, various mechanical degrees of freedomof a surgical instrument installed onto an instrument manipulator 512can be moved by operation of the teleoperated actuators of instrumentcarriage 530.

Patient Side Control of Teleoperated Instrument End Effector

As discussed previously, FIG. 1 is a plan view of an exemplary minimallyinvasive teleoperated surgical system. Referring to FIG. 1, in oneaspect, a surgeon 18 performs a medical procedure using a teleoperatedsurgical system by manipulating one or more input control devices (e.g.,input control devices 36 shown at FIG. 2) of a surgeon's console 16. Inthis manner, surgeon 18 teleoperatively controls surgical instrumentsinstalled on patient-side cart 22, which is located some distance awayfrom surgeon 18 seated at surgeon's console 16. In certain situations,however, it may be desirable for a medical person other than surgeon 18(e.g., assistants 20 at FIG. 1) to have the ability to control one ormore mechanical degrees of freedom of surgical instruments installed onpatient-side cart 22 from a location other than surgeon's console 16.For example, it may be desirable for this control of a surgicalinstrument installed on patient-side cart 22 to be from beside patient12 and patient-side cart 22 (i.e., to have patient-side control of thesurgical instrument). It may also be desirable for this control of thesurgical instruments by persons other than surgeon 18 to have minimaldisruption on surgical workflow.

FIG. 8A is a flow diagram of a control algorithm 800 implemented on aminimally invasive teleoperated surgical system. In one aspect, theteleoperated surgical system is similar to teleoperated surgical system10 at FIG. 1. Control algorithm 800 enables a medical person to control,from a location beside the patient rather than from a surgeon's console(e.g., surgeon's console 16 shown at FIG. 1), a mechanical degree offreedom of a surgical instrument (e.g., instrument 520 shown at FIG. 6)installed on a patient-side cart (e.g., patient-side cart 500 shown atFIG. 5). In one aspect, algorithm 800 is enabled only for patient-sidecart instrument manipulators that are in a soft lock state. Aninstrument manipulator is in a soft lock state when the instrumentmanipulator is commanded by software to remain stationary in space. Tosay that a manipulator is in a soft lock state is another way of sayingthat it in a software lock state. This definition of soft lock state (orsoftware lock state) can be understood in contrast to a hardware lock,in which a physical brake is used to maintain the position of one ormore movable elements. Generally, in the absence of external forces, aninstrument installed on an instrument manipulator in soft lock statedoes not experience any movement.

Referring to FIG. 1, in one aspect, computer-assisted activeteleoperation occurs when a surgeon 18 remotely controls the movement ofsurgical instruments mounted on patient-side cart 22. In one aspect,during active teleoperation, surgeon 18 manipulates one or more inputcontrol devices (e.g., input control devices 36 at FIG. 2) of asurgeon's console 16. One or more computer processors interpret themovement of the one or more input control devices, and communicate thisinformation to one or more instrument manipulators coupled to the one ormore input control devices. Teleoperated actuators located on the one ormore instrument manipulators move in response to the movements of theinput control devices. As discussed previously, a surgical instrumentcan be installed onto the instrument carriage of an instrumentmanipulator. By mechanically coupling one or more instrument inputs tocorresponding actuator outputs (e.g., actuator outputs 705 at FIG. 7) ofteleoperated actuators, various mechanical degrees of freedom of asurgical instrument installed onto an instrument manipulator can becontrolled by a surgeon 18 seated at the surgeon's console 16.

In one aspect, a computer processor of a minimally invasive teleoperatedsurgical system (e.g., a computer processor located on electronics cart24 shown at FIG. 3) queries a patient-side cart with one or moreinstrument manipulators to determine whether algorithm 800 is enabledfor each of the one or more instrument manipulators. Referring to FIG.8A, in one aspect, algorithm 800 at 810 determines if an instrumentmanipulator is in a soft lock state by determining whether a particularinstrument manipulator is receiving movement commands associated with asurgeon's manipulating one or more control inputs at a surgeon'sconsole. If the instrument manipulator is not in a soft lock state, thenat 815, instrument manipulator movement is governed by activeteleoperation control algorithms.

In one aspect, algorithm 800 determines a reference state for aninstrument manipulator. A surgical instrument is installed on theinstrument manipulator, and the manipulator is in a soft lock state.Referring to FIG. 8A, algorithm 800 at 820 determines a reference statefor a plurality of teleoperated actuators housed in the carriage portion(e.g., instrument carriage 530 at FIG. 5 and FIG. 7) of the instrumentmanipulator (e.g., instrument manipulator 520 at FIG. 5 and FIG. 7). Inone aspect, the teleoperated actuators are teleoperated servo motors,and the reference state includes the rotational position of each servomotor drive shaft (the drive shaft reference state position) and thetorque being applied by each servo motor to maintain its rotationalposition (the reference state torque). Generally, in the absence ofexternal forces, the instrument installed on the instrument manipulatorin soft lock state does not experience any movement. The instrumentmanipulator holds the instrument's mechanical degrees of freedom static,applying to each servo motor its reference state torque to maintain eachservo motor's drive shaft reference state position.

At 830, the rotational position and torque applied by each of theplurality of teleoperated servo motors is continuously monitored. One ormore instrument inputs of the surgical instrument are mechanicallycoupled to corresponding teleoperated servo motors. In one situation,external forces are applied to an end effector (e.g., end effector 654at FIG. 6) located at a distal end of the instrument, e.g., due to asecond instrument's collision with the end effector, and the externalforces applied to the end effector back-drive one or more instrumentinputs in the following manner. The external forces are transferred fromthe end effector through a drive mechanism (e.g., pullwires, tendons,pulleys, gears, etc.) of the instrument to one or more instrument inputsthat control movement of the end effector, and the forces are furthertransferred by the instrument inputs to corresponding teleoperated servomotors with which the instrument inputs are mechanically coupled.

Algorithm 800 at 840 determines that the forces transmitted to the servomotors are indicative of external forces applied to the end effector,and that the forces transmitted to the servo motors are not indicativeof a deliberate attempt by a medical person to manually actuate theinstrument end effector from the patient side. In one aspect, thisdetermination at 840 is made if two or more servo motors (as opposed toonly a single servo motor) experience force perturbations that cause thetwo or more servo motors to be incapable of maintaining their respectivedrive shaft reference state positions without applying torques in excessof their respective reference state torques. In such case, algorithm 800proceeds to 850, at which all servo motors of the instrument carriageonto which the instrument is installed are commanded to remain in thesoft lock state. Each servo motor is generally commanded to maintain itsdrive shaft reference state position, applying additional torque asnecessary to counteract the external force. In this manner, the positionand orientation of the instrument end effector is maintained despite theexternal force applied to the instrument end effector.

In one aspect, a torque limit exists for at least one of the servomotors. If an external force causes a servo motor with a torque limit tobe acted upon by a torque in excess of this torque limit, the servomotor will be incapable of resisting the torque generated by theexternal force. One way of implementing a torque limit for a servo motoris through software control. Each servo motor can include a rotaryencoder that is capable of detecting the rotational position of thedrive shaft of the servo motor. The torque applied by the servo motor isa function of the electrical current supplied to the servo motor.Accordingly, the servo motors can be controlled using the drive shaftrotational position and the electrical current supplied to the servomotor. For example, 1 ft-lb torque limit implemented using softwarecontrol can be set for a servo motor. Accordingly, the servo motor canbe commanded to maintain its rotational position subject to an upperlimit to the electrical current applied to the servo motor. This upperlimit to the electrical current corresponds to the 1 ft-lb torque limit.If the servo motor is exposed to external forces that causes it to besubject to greater than 1 ft-lb of torque, the torque limit precludesthe servo motor from maintaining is rotational position. As a result,the servo motor will be back driven away from the rotational position itwas trying to maintain. If the torque that the servo motor is subject todrops below 1 ft-lb, then the servo motor is again able to return to therotational position it was trying to maintain.

In one aspect, a surgical instrument (e.g., surgical instrument 520 atFIG. 6) provided for use with a minimally invasive teleoperated surgicalsystem includes mechanical features for manual actuation of an endeffector of the surgical instrument. The mechanical features can includea lever (e.g., lever 910 at FIG. 9A) operable by a medical person toactuate an instrument end effector. Alternatively, the mechanicalfeatures can include a socket head feature (e.g., socket head feature1020 a at FIG. 10B) with which a hex wrench can be engaged to rotate arotatable member. The lever or socket head feature can be mechanicallycoupled to an instrument input by a mechanism including at least one ofa pullwire, tendon, pulley, gears, etc. When the surgical instrument isinstalled for use on a teleoperated surgical system, the instrumentinput is mechanically coupled to a servo motor. Additional aspects ofvarious mechanical features for manual end effector actuation will bediscussed in greater detail later with reference to FIGS. 9-12.

In one aspect, a teleoperated surgical system is configured to allow amedical person to use manually actuate an end effector of a surgicalinstrument while the instrument is installed on a patient-side cartinstrument manipulator, provided that the instrument manipulator is inthe soft lock state. A medical person can apply an external force to amechanical feature of a surgical instrument (e.g., lever 910 at FIG. 9A,socket head feature 1020 a at FIG. 10B, etc.) configured to providemanual actuation of an end effector of the surgical instrument, whilethe surgical instrument is installed on a patient-side cart instrumentmanipulator. As discussed previously, when a surgical instrument isinstalled for use on a teleoperated surgical system, one or moreinstrument inputs are mechanically engaged with corresponding actuatoroutputs of servo motors. Accordingly, the external force applied by themedical person is mechanically transmitted (e.g., by pullwires, tendons,pulleys, gears, etc.) to an instrument input, which in turn transmits aforce to a teleoperated servo motor with which the instrument input ismechanically coupled.

In one aspect, algorithm 800 at 840 detects that one servo motor (asopposed to two or more servo motors) experiences force perturbationsthat cause the one servo motor to be incapable of maintaining its driveshaft reference state position without applying torque in excess of itsrespective reference state torque, and determines that this isindicative of a deliberate attempt by a medical person to manuallyactuate the instrument from the patient side (i.e., it is not indicativeof an external force applied to an end effector of the instrument). Insuch case, algorithm 800 proceeds to 860, at which the one servo motoris commanded to discontinue soft lock state behavior. The behavior ofthe other servo motors are not affected. They remain in the soft lockstate, in which they are commanded to apply additional torque asnecessary to maintain their respective drive shaft reference statepositions. For the one servo motor, that one servo motor will not becommanded to apply larger torque in order to maintain its drive shaftreference state position. In one aspect, power to this one servo motorwill be cut off. Accordingly, the external force applied by the medicalperson to manually actuate the end effector overcomes any passiveresistance of the powered-off servo motor and successfully actuates theend effector.

In another aspect, after a servo motor is commanded to discontinue softlock behavior at 860, algorithm 800 at 861 may optionally (as indicatedby dashed line) command the servo motor to apply a torque to resist ordampen the effects of external forces applied by a medical person tomanually actuate the end effector. This torque applied by the servomotor is in a direction opposite to and has a magnitude that is lessthan the torque acting on the servo motor as a result of the externalforces applied by the medical person. Application of thisresistive/dampening torque enables an enhanced degree of control overthe speed at which manual actuation of the instrument end effector takesplace. For instance, while cutting power to the servo motor is alonesufficient to allow a medical person to back-drive the servo motor andmanually actuate the end effector, the teleoperated surgical system onwhich algorithm 800 is implemented retains no control over the speed atwhich the manual actuation of the end effector takes place. In contrast,if algorithm 800 includes 861, the servo motor can, e.g., apply a torquehaving an appropriate magnitude to slow down a manual actuation by amedical person when the algorithm detects an attempted manual actuationof the end effector that is quicker than preferred for safety purposes.This aspect is further discussed later with reference to FIGS. 9A-9B.

In one aspect, after a servo motor is commanded to discontinue soft lockbehavior at 860, algorithm 800 at 862 may optionally (as indicated bydashed line) instruct the teleoperated surgical system to provide anotification that a medical person is attempting to manually actuate theend effector of an instrument installed for use on the teleoperatedsurgical system. Referring to FIGS. 1-3, this notification can be avisual notification provided to surgeon 18 via at least one of left eyedisplay 32 and right eye display 34 of surgeon's console 16. Thisnotification can also be a visual notification provided via a visualdisplay of electronics cart 24. This notification can also be anauditory notification, e.g., in the form of a warning message that canbe heard by an operating surgeon or by all members of a surgical team.

In one aspect, a surgical instrument installed for use on a teleoperatedsurgical system implementing algorithm 800 includes an end effectorhaving multiple mechanical degrees of freedom that are operated by twoor more instrument inputs. FIGS. 11A-11C and 12A-12C show variousaspects of this type of surgical instrument. When the surgicalinstrument is installed for use on a teleoperated surgical system, thetwo or more instrument inputs that operate the multiple mechanicaldegrees of freedom are mechanically engaged with corresponding servomotors.

In one aspect, a medical person desires to manually actuate the multiplemechanical degrees of freedom of the instrument end effector from thepatient side, while the instrument is installed on the teleoperatedsurgical system. In one aspect, the medical person manually actuates themultiple mechanical degrees of freedom by applying a first externalforce to a first mechanical feature mechanically coupled to a firstinstrument input by a mechanism including at least one of a pullwire,tendon, pulley, gears, etc., and then applying a second external forceto a second mechanical feature similarly coupled to a second instrumentinput. One or more additional mechanical features similarly coupled toadditional instrument inputs may be included. Accordingly, in oneaspect, after a first servo motor is commanded to discontinue soft lockbehavior at 860, algorithm 800 at 863 may optionally (as indicated bydashed line) command one or more additional servo motors to discontinuesoft lock behavior. In one aspect, power to the first servo motor andthe one or more additional servo motors will be cut off. In this manner,the external forces applied by the medical person (e.g., the firstexternal force and the second external force) to manually actuate theend effector overcomes any passive resistance of powered-off servo motorand successfully actuates the multiple degrees of freedom in series.Various aspects are discussed later in greater detail with reference toFIGS. 12A-12C.

In one aspect, a surgical instrument installed for use on a teleoperatedsurgical system implementing algorithm 800 includes an end effectorhaving two independently controllable mechanical degrees of freedom. Onexample of such a surgical instrument is a two-jaw instrument, in whichthe movement of each of the two jaws is controlled by a separateinstrument input of an instrument proximal control mechanism (e.g.,proximal control mechanism 640 at FIG. 6). One embodiment of a two-jawinstrument proximal control mechanism is shown at FIGS. 11A-11C.

In one aspect, a two-jaw instrument of the type described above isinstalled for use on a teleoperated surgical system. A medical personapplies an external force to a mechanical feature of the two-jawinstrument configured to provide manual actuation one of the two jaws.This external force applied by the medical person is mechanicallytransmitted (e.g., by pullwires, tendons, pulleys, gears, etc.) to afirst instrument input, which in turn transmits a force to acorresponding first teleoperated servo motor. Consistent with earlierdiscussions with reference to 840 and 860, in one aspect, the firstteleoperated servo motor is commanded to discontinue soft lock behaviorat 860.

In one aspect, when a medical person desires to manually actuate an endeffector of a two-jaw instrument from the patient side, it is desirablefor both jaws of the two-jaw instrument to be actuated in a symmetricalmanner. After a first servo motor is commanded to discontinue soft lockbehavior at 860, algorithm 800 at 863 may optionally (as indicated bydashed line) command a second servo motor to discontinue soft lockbehavior. The first servo motor is associated with a first instrumentinput that operates a first jaw member, and the second servo motor isassociated with a second instrument input that operates a second jawmember. An external force applied by the medical person is mechanicallytransmitted (e.g., by pullwires, tendons, pulleys, gears, etc.) to afirst instrument input, which in turn transmits the force to acorresponding first servo motor. This external force moves the first jawmember, overcoming any resistance provided by the first servo motor.

In one aspect, a controller monitors the change in rotational positionof the first servo motor as it is acted upon by the medical person'smanual actuation. Additionally, as indicated by dashed line, algorithm800 at 864 may optionally actively command the second servo motor tomirror the first servo motor's change in rotational position.Accordingly, as a medical person manually actuates a movement of a firstjaw member of a two instrument installed for use on a teleoperatedsurgical system, the teleoperated surgical system commands a movement ofa second jaw member of the two-jaw instrument. In one aspect, thesemovements produce a symmetric opening of the first jaw member and thesecond jaw member. Aspects of 864 are discussed in greater detail laterwith reference to FIGS. 11A-11C.

In one aspect, after a servo motor is commanded to discontinue soft lockbehavior at 860 and after a medical person manually actuates an endeffector mechanical degree of freedom associated with the servo motor,the teleoperated surgical system implementing algorithm 800 allows theinstrument to immediately return to teleoperative control. Referring toFIG. 1, in one aspect, assistant 20 manually actuates the end effectorof an instrument 26 in a manner consistent with the foregoingdiscussion. Upon assistant 20 completing the manual actuation of the endeffector, surgeon 18 seated at surgeon's console 16 is immediately ableto teleoperatively control instrument 26, with no disruption to thesurgical workflow.

FIG. 8B is a flow diagram of a control algorithm 1800 implemented on aminimally invasive teleoperated surgical system. In one aspect, theteleoperated surgical system is similar to teleoperated surgical system10 at FIG. 1. Like control algorithm 800 shown at FIG. 8A, controlalgorithm 1800 enables a medical person to control, from thepatient-side, a mechanical degree of freedom of a surgical instrument(e.g., instrument 520 shown at FIG. 6) installed on a patient-side cart(e.g., patient-side cart 500 shown at FIG. 5).

Referring to FIG. 8B, at 1810, algorithm 1800 detects that a surgicalinstrument has been installed onto a carriage of a manipulator locatedon the patient-side cart of a teleoperated surgical system. Installationof the surgical instrument onto the carriage activates a sensor locatedon the manipulator. In one example, the sensor is a switch, andinstallation of the surgical instrument moves the switch from an OFFposition to an ON position. Movement of the switch into the ON positioncauses the sensor to communicate a signal to the computer processorimplementing algorithm 1800, informing it that a surgical instrument hasbeen installed. In another instance, the sensor is a Hall effect sensorhoused in the carriage, and the surgical instrument includes a magnetconfigured to interact with the Hall effect sensor. When the surgicalinstrument is installed on the manipulator, the magnet on the surgicalinstrument is brought into proximity with the Hall effect sensor. Theproximity of the magnet causes the Hall effect sensor to communicate asignal to the computer processor implementing algorithm 1800, informingit that a surgical instrument has been installed.

In one aspect, installing the surgical instrument onto the manipulatormechanically couples one or more instrument inputs to correspondingactuator outputs (e.g., actuator outputs 705 at FIG. 7) of teleoperatedactuators. The teleoperated actuators can be servo motors. Duringcomputer-assisted teleoperation, servo motors of the manipulator move inresponse to the movements of input control devices accessible to a userof the teleoperated surgical system. In this manner, various mechanicaldegrees of freedom of the surgical instrument can be controlled by asurgeon seated at a surgeon's console. See portions of this DetailedDescription relating to FIGS. 1-7 for details. The surgical instrumentcan also include a memory device. Installing the surgical instrumentonto the manipulator puts the memory device in data communication with acomputer processor of the teleoperated surgical system. The memorydevice includes preprogrammed information, which once communicated tothe teleoperated surgical system, is used to enable thecomputer-assisted teleoperation of the surgical instrument. Thepreprogrammed information is stored on the memory device of the surgicalinstrument at the time of the surgical instrument's manufacture.

At 1820, algorithm 1800 queries the memory device of the installedsurgical instrument, whose preprogrammed information is communicated tothe computer processor implementing algorithm 1800. In one aspect, thepreprogrammed information communicated to the computer processorincludes the type of the surgical instrument. The preprogrammedinformation can also include certain information used to enablecomputer-assisted teleoperation of the surgical instrument, such asinformation about the surgical instrument movements controlled byindividual instrument inputs and their corresponding servo motors of themanipulator. For example, for a first instrument type, this informationcan include the following: (1) the instrument includes five movableinstrument inputs numbered #1 through #5; (2) instrument input #1 ismechanically coupled to the mechanical degree of freedom of interest,here a mechanical degree of freedom of an end effector of the surgicalinstrument; and (3) instrument input #1 is mechanically driven by acorresponding servo motor #1. As another example, for a secondinstrument type, this information can include the following: (1) theinstrument includes four movable instrument inputs numbered #1 through#4; (2) instrument input #4 is mechanically coupled to the mechanicaldegree of freedom of interest, here a mechanical degree of freedom thatorients the end effector relative to the rest of the instrument; and (3)instrument input #4 is mechanically driven by a corresponding servomotor #4. In one aspect, at 1820, algorithm 1800 queries the memorydevice of the surgical instrument to determine the type of surgicalinstrument installed and the associated information.

At 1830, algorithm 1800 programs a manipulator control input located onan instrument manipulator of the teleoperated surgical system using tothe instrument information received from the memory device of theinstalled instrument. In one aspect, the manipulator control input isprogrammed so that activating the control input commands one servo motorof the carriage controlling a mechanical degree of freedom of interestto discontinue soft lock state behavior. In one aspect, power to thisservo motor is cut off. In one instance, the surgical instrumentmechanical degree of freedom of interest is a mechanical degree offreedom of a surgical instrument end effector. In another instance, thesurgical instrument mechanical degree freedom of interest orients thesurgical instrument end effector relative to the rest of the instrument.

At 1840, algorithm 1800 detects that a user has activated themanipulator control input of an instrument manipulator with aninstrument installed onto its carriage. At 1850, algorithm 1800 queriesthe instrument manipulator to determine whether it is in a soft lockstate. If it is determined that the instrument manipulator is not in asoft lock state, algorithm 1800 proceeds to 1855, at which a message iscommunicated to one or more users of the teleoperated surgical systemthat the programmed function of the manipulator control input cannot beaccessed because the manipulator is under the active control of asurgeon from the surgeon's console. In one aspect, this communication isin the form of a message displayed on one or more displays of theteleoperated surgical system. In another aspect, this communication isauditory (e.g., a voice message, an error beep, etc.). In contrast, ifit is determined that the algorithm is in a soft lock state, thenalgorithm 1800 will allow the programmed function of the manipulatorcontrol input to be accessed, and proceeds to 1860. In one aspect, themanipulator control input is programmed to discontinue the supply ofpower to servo motor #1, which operates a grip mechanism of theinstalled surgical instrument.

Optionally, as indicated by dashed line, at 1861, algorithm 1800communicates to one or more users of the teleoperated surgical systemthat it is now possible to manually actuate a grip mechanism of theinstalled surgical instrument from the patient-side.

First Example

FIG. 9A shows a perspective view of a surgical instrument 900. FIG. 9Bshows a view of instrument 900 looking from the distal 902 directiontowards the proximal 901 direction. In one aspect, consistent with theforegoing discussion, instrument 900 is removably coupled to aninstrument carriage (similar to instrument carriage 530 at FIG. 7) of aninstrument manipulator. The instrument carriage includes a plurality ofservo motors. Each of instrument inputs 940 b,941,942,944,948 ismechanically coupled with one of a plurality of actuator outputs(similar to actuator outputs 705 at FIG. 7) of the servo motors.Accordingly, rotation of a servo motor rotates its associated actuatoroutput 705, which in turn rotates a corresponding instrument input(i.e., one of instrument inputs 940 b,941,942,944,948).

Rotation of instrument input 940 b by a corresponding servo motor opensand closes a jaw-type end effector of instrument 900. Rotation ofinstrument input 940 b turns input shaft 940. Cable segment 930 a iscoupled to member 920 a. Rotation of input shaft 940 in a firstdirection will increase tension in cable segment 930 a and reducetension in cable segment 930 b, moving member 920 in the proximaldirection and applying a force to close the end effector jaws ofinstrument 900. Rotation of input shaft 940 in a second direction willincrease tension in cable segment 930 b and reduce tension in cablesegment 930 a, moving member 920 in the distal direction and applying aforce to open the end effector jaws of instrument 900.

In one aspect, instrument 900 is installed on an instrument carriagecomponent of an instrument manipulator, and instrument inputs 940 b,941, 942, 943, 944 are mechanically coupled to corresponding servomotors of the carriage portion of the instrument manipulator. The servomotors of the instrument manipulator are in a soft lock state, and notbeing actively controlled by a surgeon or other medical person. Areference state is determined for the plurality of servo motors ofinstrument carriage. The reference state notes for each servo motor therotational position of the servo motor drive shaft and the torque beingapplied by the servo motor to maintain the position of the motor.

In one aspect, a medical person located at the patient side desires toopen the end effector jaws of instrument 900 while instrument 900 isinstalled for use on the instrument carriage. Referring to FIG. 9A, inone aspect, the medical person opens the end effector jaws of instrument900 by actuating lever 910. Lever 910 is coupled to member 910 a.Actuating lever 910 by moving it in the distal 902 direction causesmember 910 a to pivot about axis 910 b. The pivoting of member 910 aproduces a movement of member 910 a that is generally in the distal 902direction. This distal movement is transferred to elongate member 920 byfeature 920 a. Elongate member 920 transmits this force down the shaft990 of the instrument to actuate end effector jaws of instrument 900.Actuating lever 910 by moving it in the distal 902 direction alsoapplies cable tension to cable segment 930 a and releases cable tensionin cable segment 930 b. This in turn causes cable to unwind from capstan940 a as input shaft 940 rotates. The rotational force applied to inputshaft 940 is transmitted via instrument input 940 b (directly, orthrough an intermediate interface) to a corresponding servo motor ininstrument carriage 705.

In one aspect, the instrument manipulator to which instrument 900 isinstalled is in a soft lock state. Generally, in the soft lock state, acontroller of the instrument manipulator commands each servo motor ofthe instrument manipulator to maintain each servo motor's drive shaftrotational position. If the servo motor operatively coupled toinstrument input 940 b remains in a soft lock state when a medicalperson actuates lever 910, then the associated servo motor will simplybe commanded to increase the amount of motor torque applied an equal andopposite amount, so as to maintain the servo motor at its drive shaftreference state position. If the servo motor operatively coupled toinstrument input 940 b stays in a soft lock state, the medical personactuating lever 910 will likely be unable to open the end effector jawsof instrument 900, unless he applies sufficient torque throughinstrument input 940 b to overcome a torque limit of the associatedservo motor.

In one aspect, as discussed in the context of algorithm 800 withreference to FIG. 8A, certain conditions detectable at the servo motorsare indicative of a medical person attempting to operate the endeffector from the patient side. In such case, a controller of theinstrument manipulator will disable soft lock in one or more servomotors so as to enable an external force applied by a medical person toback-drive the one or more servo motors. Referring to FIG. 9A, in oneaspect, instrument input 944 is configured to rotate instrument shaft990 about an instrument shaft longitudinal axis. In one aspect,instrument 900 is installed on and operatively coupled to an instrumentcarriage of an instrument manipulator in a soft lock state. Uponentering soft lock state, a reference state is taken, including thedrive shaft rotational position (drive shaft reference state position)of each of the servo motors of the instrument carriage and the torqueapplied by each of the servo motors (reference state torque) to maintainits respective drive shaft reference state position.

After the drive shaft reference state position and the reference statetorque of each servo motor are taken, a medical person applies anexternal force via lever 910 that acts on the servo motor correspondingto instrument input 940 b. The external force cause the servo motor tobe incapable of maintaining its drive shaft reference state positionwithout applying torque in excess of its reference state torque. In oneaspect, the controller further detects that the drive shaft rotationalposition of the servo motor corresponding to instrument input 944(instrument shaft roll) is unchanged from its drive shaft referencestate position, and that the torque applied by the servo motorcorresponding to instrument input 944 remains its reference statetorque. In response, the servo motor mechanically coupled to instrumentinput 940 b is commanded to discontinue soft lock state behavior. In oneaspect, power to the servo motor is cut off. Accordingly, the externalforce applied by the medical person's actuation of lever 910 overcomesany passive resistance of the powered-off servo motor and successfullyopens the end effector jaws of instrument 900.

In one aspect, after a particular servo motor is commanded todiscontinue soft lock state behavior, power to the servo motor is notcut off. Instead, the servo motor is commanded to actively apply atorque to resist the back-driving of the instrument input coupled to theservo motor, similar to 861 at FIG. 8A. For instance, referring to FIG.9A and FIG. 9B, in one aspect, a medical person actuates lever 910 andapplies an external force to instrument input 940 b, acting on it torotate in a counterclockwise direction (when viewed from the distal 902direction looking towards the proximal 901 direction). In one aspect,the servo motor associated with instrument input 940 b is commanded todiscontinue soft lock state behavior. In lieu of soft lock statebehavior, in which the servo motor is generally commanded to maintainthe drive shaft reference state position of the servo motor, the servomotor is instead commanded to apply a torque to resist, but not defeat,the rotation of instrument input 940 b resulting from the medicalperson's actuation of lever 910. In one aspect, the purpose of thisbehavior is to provide a dampening effect to slow down the rate at whichinstrument input 940 b is rotated. Because the rotation of instrumentinput 940 b is operatively coupled to the opening of the end effectorjaws of instrument 900, the ultimate effect of the slowing down therotation of instrument input 940 b is to slow down the opening of endeffector jaws of instrument 900 when lever 910 is actuated.

Second Example

FIG. 10A shows a perspective view of a surgical instrument 1000. FIG.10B shows a perspective view of instrument 1000 with instrument cover1011 removed. FIG. 10C shows a view of instrument 1000 from a distal1002 direction looking towards a proximal 1001 direction. In one aspect,instrument 1000 is removably coupled to the instrument carriage of aninstrument manipulator, the instrument carriage housing a plurality ofservo motors. Each of instrument inputs 1020 c, 1021, 1022 ismechanically coupled to one of the plurality of servo motors.Accordingly, rotation of one the servo motors rotates a correspondinginstrument input (i.e., one of instrument inputs 1020 c, 1021, 1022). Inone aspect, rotation of instrument input 1020 c by a corresponding servomotor moves an end effector jaw of instrument 1000.

Referring to FIG. 10B, rotating instrument input 1020 c rotates inputshaft 1020. Input shaft 1020 includes geared surface 1020 b, whichengages complimentary gear surface 1030 a of pivoting member 1030. Wheninput shaft 1020 rotates, pivoting member 1030 rotates about axis 1030b. Pivoting member 1030 is coupled to elongate member 1040, which iscoupled to an end effector of instrument 1000. Translation of theelongate member 1040 in a proximal 1001 direction moves a jaw of the endeffector in a closing direction, and translation of the elongate member1040 in a distal 1002 direction moves the jaw of the end effector in anopening direction. Instrument inputs 1021 and 1022 are configured torotate instrument shaft 1090 about an instrument shaft longitudinalaxis.

In one aspect, an instrument manipulator on which instrument 1000 isinstalled is in a soft lock state and not under the active control of asurgeon or other medical person. A reference state for the servo motorsof the instrument carriage is determined, including the drive shaftrotational position of each servo motor (the drive shaft reference stateposition) and the torque being applied by each servo motor (thereference state torque) to maintain its respective drive shaft referencestate position.

Referring to FIG. 10A, in one aspect, a medical person located at thepatient side desires to open the end effector jaw of instrument 1000from the patient side. The medical person inserts a hex wrench throughopening 1010 of instrument cover 1011. The hex wrench is sized tointerface with socket head feature 1020 a of input shaft 1020. Once thehex wrench is properly inserted into socket head feature 1020 a,rotating the hex wrench in a counterclockwise direction (when viewedfrom the proximal 1001 direction looking towards the distal 1002direction) will apply a rotational force to input shaft 1020, which inturn rotates instrument input 1020 c.

In one aspect, instrument 1000 is coupled to the instrument carriageportion of an instrument manipulator. A medical person applies arotational force to instrument input 1020 c, which in turn applies arotational force to a servo motor mechanically coupled to instrumentinput 1020 c. A controller of the instrument manipulator detects thatthe servo motor corresponding to instrument input 1020 c is applyingelevated torque levels to maintain its reference state motor position.The controller further detects that the drive shaft rotational positionof the servo motor corresponding to at least one of instrument input1021 (instrument shaft roll) and instrument input 1022 (instrument shaftroll) is unchanged from its drive shaft reference state position, andthat the torque applied by the servo motors corresponding to instrumentinputs 1021 and 1022 remains their respective reference state torques.In response, the servo motor associated with instrument input 1020 c iscommanded to discontinue soft lock state behavior. In one aspect, powerto the servo motor is cut off. Accordingly, the external force appliedby the medical person using the hex wrench overcomes any passiveresistance of the powered-off servo motor and successfully opens thegrip mechanism of instrument 1000.

Third Example

FIG. 11A shows a perspective view of a surgical instrument 1100. FIG.11B shows a perspective view of instrument 1100 with instrument cover1111 shown transparently. FIG. 11C shows instrument 1100 viewed from thedistal 1102 direction looking towards the proximal 1101 direction. Inone aspect, instrument 1100 is removably coupled to an instrumentcarriage portion of an instrument manipulator, the instrument carriagehousing a plurality of servo motors. Each of instrument inputs 1120b,1140 b,1121,1122,1123 is mechanically coupled to one of the pluralityof servo motors. Accordingly, rotation of one of the servo motorsrotates a corresponding instrument input (i.e., one of instrument inputs1120 b,1140 b,1121,1122,1123). Referring to FIG. 11C, in one aspect, anend effector of instrument 1100 is a two jaw end effector. Each jaw ofthe two jaw end effector is independently controlled by an instrumentinput. A first jaw is operated by instrument input 1120 b, and a secondjaw is operated by instrument input 1140 b.

Referring to FIG. 11B-11C, rotating instrument input 1123 rollsinstrument shaft 1190 of instrument 1100 about an instrument shaftlongitudinal axis. Rotating instrument input 1140 b in a first directionrotates input shaft 1140 in the first direction. This increases tensionin cable segment 1131 a and reduces tension in cable segment 1131 b.These tensions are transferred, via one or more idler pulleys 1135, to afirst jaw of the two-jaw end effector located at a distal end ofinstrument shaft 1190, producing a movement in an opening direction forthe first jaw. Rotating 1140 b in a second direction increases tensionin cable segment 1131 b and reduces tension in cable segment 1131 a.This accordingly produces a movement in a closing direction for thefirst jaw.

Similarly, with respect to instrument input 1120 b, rotating instrumentinput 1120 b in a first direction rotates input shaft 1120 in the firstdirection. This increases tension in cable segment 1130 a and reducestension in cable segment 1130 b. These tensions are transferred, via oneor more idler pulleys 1135, to a second jaw of the two-jaw end effectorlocated at the distal end of instrument shaft 1190, producing a movementin the opening direction for the second jaw. Rotating 1140 b in a seconddirection increase tension in cable segment 1130 b and reduces tensionin cable segment 1130 a. This accordingly produces a movement in aclosing direction for the second jaw.

The coordinated motion of instrument input 1120 b and instrument input1140 b synchronously open and close the two jaws of the instrument 1100end effector. In one aspect, to open the jaws, instrument input 1120 band instrument input 1140 b are rotated in the first direction atsubstantially the same rate. To close the grippers, instrument input1120 b and instrument input 1140 b are rotated in the second directionat substantially the same rate.

In one aspect, instrument 1100 is removably coupled to an instrumentcarriage portion of an instrument manipulator, and each of instrumentinputs 1120 b, 1140 b, 1021, 1022, 1123 is mechanically coupled to oneof a plurality of servo motors housed in the instrument carriage.Accordingly, rotation of one of the servo motors rotates a correspondinginstrument input (i.e., one of instrument inputs 1120 b, 1140 b, 1021,1022, 1123). In one aspect, instrument manipulator to which instrument1100 is coupled is in a soft lock state and is not under active controlby a surgeon or other medical person. A reference state for the servomotors of the instrument carriage is determined, including the driveshaft rotational position of each servo motor (the drive shaft referencestate position) and the torque being applied by each servo motor (thereference state torque) to maintain its respective drive shaft referencestate position.

Referring to FIG. 11A, in one aspect, a medical person located at thepatient side, desires to open the end effector mechanism of instrument1100 from the patient side. In one aspect, the medical person inserts asuitably sized hex wrench through opening 1110 of instrument cover 1111to interface with socket head feature 1120 a of input shaft 1020. Oncethe hex wrench is properly seated in socket head feature 1020 a, themedical person applies a rotational force to input shaft 1020 byrotating the hex wrench in a counterclockwise direction (viewed from aproximal 1001 direction looking towards a distal 1002 direction).

A controller of the instrument manipulator detects that the servo motoris being acted upon by an external force. The external force applied bythe medical person causes the servo motor to be incapable of maintainingits drive shaft reference state position without applying torque inexcess of its reference state torque. In one aspect, the controllerfurther detects that the rotational position of the servo motorcorresponding to instrument input 1123 (instrument shaft roll) isunchanged from its drive shaft reference state position, and that thetorque applied by the servo motor corresponding to instrument input 1123remains its reference state torque.

In response, the controller of the instrument manipulator commands theservo motor corresponding to instrument input 1020 c to discontinue softlock state behavior. This permits the medical person to move the secondjaw of the two end effector in an opening direction. In one aspect, thecontroller of the instrument manipulator commands a complementary,coordinated motion of the servo motor mechanically coupled to instrumentinput 1140 b at the same time or nearly the same time the medical personmoves the second jaw in the opening direction. Accordingly, thecontroller of the instrument manipulator commands the servo motormechanically coupled to instrument input 1140 b to move the first jaw inan opening direction at the same time as the medical person uses a hexwrench to move the second jaw of the two end effector in an openingdirection. The effect of this coordination is that the first jaw and thesecond jaw of the two end effector open at substantially the same ratein a symmetric manner.

Fourth Example

FIG. 12A shows a perspective view of a surgical instrument 1200. FIG.12B shows a perspective view of instrument 1200 with instrument cover1211 removed. FIG. 11C shows a view of instrument 1200 from the distal1202 direction looking towards the proximal 1201 direction. In oneaspect, instrument 1200 is removably coupled to the instrument carriageportion of an instrument manipulator, the instrument carriage includinga plurality of servo motors. Each of instrument inputs 1220 b, 1250 b,1270 b, 1271, 1272 is mechanically coupled to one of the plurality ofservo motors. Accordingly, rotation of a servo motor rotates acorresponding instrument input (i.e., one of instrument inputs 1220 b,1250 b, 1270 b, 1271, 1272).

In one aspect, the end effector of instrument 1200 includes threemechanical degrees of freedom. A first mechanical degree of freedom is alow force jaw opening and closing mechanism that is operatively coupledto instrument input 1270 b. A second mechanical degree of freedom and athird mechanical degree of freedom of the end effector are operativelycoupled to the complementary operation of instrument inputs 1220 b and1250 b. In one example, the second mechanical degree of freedom is ahigh force jaw closing mechanism, and the third mechanical degree offreedom enables stapler firing and tissue transecting.

In one aspect, instrument input 1220 b operates a switching mechanism,whose rotational position determines which of a plurality of mechanicaldegrees of freedom is operatively coupled to the rotation of instrumentinput 1250 b. Rotating instrument input 1220 b to a first positionoperatively couples instrument input 1250 b to a mechanical degree offreedom that provides high force jaw closing of the end effector locatedat the distal end of instrument shaft 1290. This high-force closingmechanism is complementary to the low force jaw grip opening and closingmechanism operatively coupled to instrument input 1270 b. Rotatinginstrument input 1220 b to a second position operatively couplesinstrument input 1250 b to a mechanical degree of freedom that providesstapler firing and tissue transecting functionality at the end effectorof instrument 1200. Rotating instrument input 1220 b to a third positionoperatively couples instrument input 1250 b to a mechanical degree offreedom that provides for rotation of instrument shaft 1290 about ashaft longitudinal axis.

In one aspect, instrument 1200 is removably coupled to the instrumentcarriage portion of an instrument manipulator, and each of instrumentinputs 1220 b, 1250 b, 1270 b, 1271, 1272 is mechanically coupled to oneof a plurality servo motors. In one aspect, the instrument manipulatoron which instrument 1200 is installed is in a soft lock state and is notunder the active control of a surgeon or other medical person. Areference state for the servo motors of the instrument carriage isdetermined, including the drive shaft rotational position of each servomotor (the drive shaft reference state position) and the torque beingapplied by each servo motor to maintain its respective drive shaftreference state position (the reference state torque).

Referring to FIG. 12A, in one aspect, a medical person located at thepatient side desires to opens the end effector mechanism of instrument1200 from the patient side by inserting a hex wrench through opening1210 of instrument cover 1211. The hex wrench is sized to interface withsocket head feature 1220 a of input shaft 1220. Once the hex wrench isproperly seated in socket head feature 1220 a, the medical person canrotate the hex wrench in a counterclockwise direction (viewed from theproximal 1201 direction looking towards the distal 1202 direction) toapply a rotational force to input shaft 1220.

In one aspect, a controller of the instrument manipulator detects theforce applied by the medical person in the form of a force acting on theservo motor associated with instrument input 1220 b. The external forceapplied by the medical person causes the servo motor to be incapable ofmaintaining its drive shaft reference state position without applyingtorque in excess of its reference state torque. The controller furtherdetects that the rotational position of the servo motor corresponding toinstrument input 1250 b is unchanged from its drive shaft referencestate position, and that the torque applied by the servo motorcorresponding to instrument input 1250 b remains its reference statetorque. In one aspect, the controller of the instrument manipulatorresponds to these conditions by commanding three servo motors todiscontinue soft lock state behavior: the servo motor mechanicallycoupled to instrument input 1220 b; the servo motor mechanically coupledto instrument input 1250 b; and the servo motor mechanically coupled toinstrument input 1270 b. In one aspect, power is cut off to all threeservo motors.

In one aspect, the medical person uses the hex wrench inserted intosocket head feature 1220 a to rotate input shaft 1220 into the firstposition. Using the hex wrench, the medical person is able to apply anexternal force to instrument input 1220 b, which is transmitted to theservo motor mechanically coupled to instrument input 1220 b. In oneaspect, the servo motor mechanically coupled to instrument input 1220 bhad earlier been commanded to discontinue soft lock state behavior.Further, power was cut off to the servo motor. Accordingly, the externalforce applied by the medical person using the hex wrench can overcomeany passive resistance of the powered-off servo motor. When input shaft1220 is in the first position, instrument input 1250 b is operativelycoupled to a mechanical degree of freedom that provides high forceclosing of an end effector at the distal end of instrument shaft 1290.

In one aspect, a protective element 1220 c is configured to occludeopening 1230, and prevent access to socket head feature 1240 a. Use of ahex wrench to rotate socket head feature 1220 a into the first positionmoves the protective element 1220 c and allows access by the hex wrenchto socket head feature 1240 a. This permits the medical person toinserts the hex wrench through opening 1230 to engage with socket headfeature 1240 a. Socket head feature 1240 a is operatively coupled toinput shaft 1250 via gear 1240. Input shaft 1250 is further coupled toinstrument input 1250 b, which is mechanically coupled to acorresponding servo motor. In one aspect, the servo motor mechanicallycoupled to instrument input 1250 b had earlier been commanded todiscontinue soft lock state behavior. Further, power was cut off to theservo motor. Accordingly, the external force applied by the medicalperson using the hex wrench can overcome any passive resistance of thepowered-off servo motor mechanically coupled to instrument input 1250 b.Thus, the medical person is able to use the hex wrench to rotate inputshaft 1250 and corresponding instrument input 1250 b. In one aspect,rotation of the hex wrench inserted in socket head feature 1240 areleases a high force jaw closing mechanism the instrument 1200 endeffector.

In one aspect, the medical person removes the hex wrench from sockethead feature 1240 a and out of opening 1230, and inserts the hex wrenchthrough opening 1260 to engage with socket head feature 1270 a. Sockethead feature 1270 a is coupled to input shaft 1270, which is in turncoupled to instrument input 1270 b. Instrument input 1270 b is coupledto a low force end effector jaw opening and closing mechanical degree offreedom. In one aspect, the servo motor mechanically coupled toinstrument input 1270 b had earlier been commanded to discontinue softlock state behavior. Further, power was cut off to the servo motor.Accordingly, an external force applied by the medical person using thehex wrench can overcome any passive resistance of the powered-off servomotor mechanically coupled to instrument input 1250 b. In one aspect,the medical person uses a hex wrench engaged with socket head feature1270 a to rotate instrument shaft 1270, which in turn actuates the lowforce end effector jaw opening and closing degree of freedom to open theend effector.

While certain exemplary embodiments have been described and shown in theaccompanying drawings, it is to be understood that such embodiments aremerely illustrative of and not restrictive on the broad invention, andthat this invention is not limited to the specific constructions andarrangements shown and described, since various other modifications mayoccur to those of ordinary skill in the art. The description is thus tobe regarded as illustrative instead of limiting.

The invention claimed is:
 1. A method comprising: detecting, at a firstteleoperated actuator being commanded to maintain its current position,an application of an external force that is in excess of a first forcethreshold; detecting, at a second teleoperated actuator being commandedto maintain its current position, no application of external force thatis in excess of a second force threshold; and in response to thedetecting that the application of the external force at the firstteleoperated actuator is in excess of the first force threshold,terminating the command to the first teleoperated actuator to maintainits current position, wherein the first teleoperated actuator isconfigured to actuate a first mechanical degree of freedom of aninstrument and the second teleoperated actuator is configured to actuatea second mechanical degree of freedom of the instrument.
 2. The methodof claim 1, wherein the detecting, at the first teleoperated actuatorbeing commanded to maintain its current position, the application of theexternal force that is in excess of the first force threshold, comprisesdetermining an electrical current supplied to the first teleoperatedactuator.
 3. The method of claim 1, wherein the external force that isin excess of the first force threshold is caused by a user manuallyapplying a force to a component of the instrument.
 4. The method ofclaim 1, wherein the detecting, at the first teleoperated actuator beingcommanded to maintain its current position, the application of theexternal force that is in excess of the first force threshold comprises:determining a reference state position of a drive shaft of the firstteleoperated actuator; determining a reference state torque for thefirst teleoperated actuator; and detecting that the first teleoperatedactuator cannot maintain its drive shaft reference state positionwithout applying a torque greater than the reference state torque. 5.The method of claim 1, further comprising: permitting a movement of adrive shaft of the first teleoperated actuator from a reference stateposition to a second position, the movement resulting from theapplication of the external force; and commanding the first teleoperatedactuator to maintain the drive shaft at the second position when theapplication of the external force ceases.
 6. The method of claim 1,further comprising discontinuing a supply of electrical power to thefirst teleoperated actuator.
 7. The method of claim 1, furthercomprising commanding the first teleoperated actuator to apply a forceto slow down, but not prevent, a movement of the first teleoperatedactuator resulting from the application of the external force.
 8. Themethod of claim 1, further comprising presenting a notification that amanual actuation of the instrument from a patient side is beingattempted.
 9. The method of claim 1, further comprising terminating thecommand to the second teleoperated actuator to maintain its currentposition.
 10. The method of claim 1, further comprising: detecting amovement of a drive shaft of the first teleoperated actuator from areference state position to a second position, the movement resultingfrom the application of external force; and commanding a correspondingmovement of the second teleoperated actuator.
 11. A teleoperated devicecomprising: a control input; an instrument manipulator configured toreceive an instrument, the instrument manipulator including a firstteleoperated actuator and a second teleoperated actuator, the firstteleoperated actuator being configured to actuate a first mechanicaldegree of freedom of the instrument and the second teleoperated actuatorbeing configured to actuate a second mechanical degree of freedom of theinstrument; and a controller configured to control movement of theinstrument installed for use on the instrument manipulator, in responseto movement of the control input, wherein the controller is furtherconfigured to: detect, while the first teleoperated actuator is beingcommanded to maintain its current position, an application of anexternal force to the first teleoperated actuator that is in excess of afirst force threshold, detect, while the second teleoperated actuator isbeing commanded to maintain its current position, no application ofexternal force to the second teleoperated actuator that is in excess ofa second force threshold, and in response to the detecting that theapplication of the external force to the first teleoperated actuator isin excess of the first force threshold, terminate the command to thefirst teleoperated actuator to maintain its current position.
 12. Theteleoperated device of claim 11, wherein the detecting, while the firstteleoperated actuator is being commanded to maintain its currentposition, the application of the external force to the firstteleoperated actuator that is in excess of the first force threshold,comprises determining an electrical current supplied to the firstteleoperated actuator.
 13. The teleoperated device of claim 11, whereinthe external force that is in excess of the first force threshold iscaused by a user manually applying a force to a component of theinstrument.
 14. The teleoperated device of claim 11, wherein thedetecting, at the first teleoperated actuator being commanded tomaintain its current position, the application of the external forcethat is in excess of the first force threshold comprises: determining areference state position of a drive shaft of the first teleoperatedactuator; determining a reference state torque for the firstteleoperated actuator; and detecting that the first teleoperatedactuator cannot maintain its drive shaft reference state positionwithout applying a torque greater than the reference state torque. 15.The teleoperated device of claim 11, wherein the controller is furtherconfigured to: permit a movement of a drive shaft of the firstteleoperated actuator from a reference state position to a secondposition, the movement resulting from the application of the externalforce; and command the first teleoperated actuator to maintain the driveshaft at the second position when the application of the external forceceases.
 16. The teleoperated device of claim 11, wherein the controlleris further configured to discontinue a supply of electrical power to thefirst teleoperated actuator.
 17. The teleoperated device of claim 11,wherein the controller is further configured to command the firstteleoperated actuator to apply a force to slow down, but not prevent, amovement of a drive shaft of the first teleoperated actuator from areference state position to a second position, the movement resultingfrom the application of the external force.
 18. The teleoperated deviceof claim 11, wherein the controller is further configured to present anotification that a manual actuation of the instrument from a patientside is being attempted.
 19. The teleoperated device of claim 11,wherein the controller is further configured to terminate the command tothe second teleoperated actuator to maintain its current position. 20.The teleoperated device of claim 11, wherein the controller is furtherconfigured to: detect a movement of a drive shaft of the firstteleoperated actuator from a reference state position to a secondposition, the movement resulting from the application of the externalforce; and command a corresponding movement of the second teleoperatedactuator.